Oil and natural gas drilling and well sites are often located in remote areas that may be difficult to access. Usable storage space at well and drilling sites is also frequently very limited due to the terrain at the well sites or other factors related to the inaccessibility of the sites. As a result, storage space for materials necessary for drilling and mining operations is often at a premium. Improving the efficiency and use of storage space at drilling and well sites can have important economic as well as practical benefits for drilling and mining operations.
Mining companies sometimes make use of a technique termed “hydraulic fracturing” to aid in the extraction of fossil fuels from well sites. Hydraulic fracturing is the propagation of fractures in a rock layer caused by the presence of a pressurized fluid. Hydraulic fractures form naturally, as in the case of veins or dikes, and is one means by which gas and petroleum from source rocks may migrate to reservoir rocks.
In some cases, oil and gas companies may attempt to accelerate this process in order to release petroleum, natural gas, coal seam gas, or other substances for extraction, where the technique is often called “fracking” or “hydrofracking” This type of fracturing is done from a wellbore drilled into reservoir rock formations. The energy from the injection of a highly-pressurized fracking fluid creates new channels in the rock which can increase the extraction rates and ultimate recovery of fossil fuels. When done in already highly-permeable reservoirs such as sandstone-based wells, the technique is known as well stimulation. Operators typically try to maintain fracture width or slow its decline following treatment by introducing a proppant into the injected fluid. A proppant is a material, such as grains of sand, ceramic, or other particulates, that prevents the fractures from closing when the injection is stopped. Consideration of proppant strengths and prevention of proppant failure becomes more important at deeper depths where pressure and stresses on fractures are higher.
A distinction can be made between low-volume hydraulic fracturing which is used to stimulate high-permeability reservoirs and high-volume hydraulic fracturing. Low volume fracking operations may consume 20,000 to 80,000 gallons of fluid per well. High-volume hydraulic fracturing, which is used in the completion of tight gas and shale gas wells can use as much as two to three million gallons of fluid per well.
The large amount of water and proppant required in a fracking operation at a well site requires that these materials be stored close to the well site so that they may be used as needed. Typically, tractor trailer rigs are used to transport these materials to well sites. If no or insufficient storage space is available at the well site, it is oftentimes necessary to store the materials in the same tractor trailer rigs that delivered the materials to the well site. This is an inefficient and frequently cost-prohibitive solution to the storage problem because the trailers must be parked until needed. This is costly because the drivers and their trucks are forced to waste valuable time out of service. Thus, the efficient storage of materials at oil and natural gas well sites is a critical factor in the successful implementation of fracking operations—for practical and economic reasons.
The storage systems in embodiments of the instant invention are a novel and non-obvious solution to the storage problems described above.